HSO with bus voltage higher than 1000V

[RTirapegui]

Hi,

I'm using Motor Control Workbench 6.2.0 with a custom power board that supports a maximum of 1200Vdc. The motor to be controlled also supports a maximum of 1200Vdc.

When creating the project, I noticed that on the Power Supply tab, the application requires the bus voltage level to be specified within a range compatible with the power board and motor specifications, which in my case is [100 - 1200] Vdc.

However, regardless of the value set in the bus voltage level text box, the Voltage Scale field on the Speed Sensing Config. tab appears to be out of range: it indicates a maximum allowed value of 1000V.

Moreover, from the HSO startup guide, I read that the voltage scale value can't be lower than the maximum voltage that can be measured based on the hardware design (which makes sense due to internal firmware scaling).

So, I wonder if there's a way for my application to work with bus voltages in the range of (1000 - 1200] Vdc?

Is this an intentional limitation of Motor Control Workbench due to internal firmware design (perhaps related to the fixed-point resolution, etc.), or can I change the value directly in drive_parameters.h without any concern?

Thanks!

[Gael A · Accepted solution]

Hello RTirapgui,

Your application should work with higher voltage scale values, this looks like a WorkBench limitation. You would eventually run into resolution issues with high voltage scale values, because you reduce your resolution, but higher VBUS usually means higher flux, and thus lesser need for high resolution, so I guess you'll be fine.

To answer your question directly : yes, you can change the Voltage Scale directly in the FW without impacting too much the code (as long as you respect the recommendations from the HSO Startup guide, that is) 

In any case, thank you for the feedback, we will try to fix the WorkBench as quickly as possible.